The management of the quality of a wireless/wireline media signal, such as voice calls typically requires the selection of a suitable point of trade-off in a multi-dimensional optimization space. The most common practice governing the capacity/quality trade-off in a packet network, wireless or wireline, is the configuration parameter that regulates the rate of audio data loss, such as the rate of frame erasures (in wireless) or rate of packet loss (wireline). This is best exemplified in wireless networks by the Radio Network Controller (RNC) parameter that controls the average frame-erasure rate in a Code Division Multiple Access (spread spectrum) type access network. This parameter, referred to as the Block Error Rate (BLER), drives the power control algorithm that controls the wireless access network. It is usually a constant whose value is chosen by the operator of a wireless network in accordance with their selected capacity target and voice quality objective.
The traditional method of selecting a static BLER target is not adequate when the network operator wants to deliver a certain audio quality level across different call configurations. This is due to the fact that with the increased commonality of mobile-to-mobile calls as well as land-to-mobile calls traversing packet networks, the overall rate of frame erasures or lost packets is no longer determined by a single air-interface. Rather, the overall packet loss rate is the sum of the frame-erasure rates of two air-interfaces (for mobile-to-mobile calls) and the packet loss rate over the backhaul network.
The same or similar inadequacies are noted in connection with other factors that affect the audio quality, or more generally the quality of a media signal that is being carried through a communications service and delivered to the user. For example, the delay induced in the media signal as it propagates through a communications network is one of the factors that affects the media signal quality and that is not adequately managed with current technologies.
Against this background, it clearly appears that a need exists in the industry to provide improved methods and network devices to better manage the audio quality during voice calls.